This invention relates to a stabilizer composition, to a polyether polyol stabilized against degradation by the stabilizer composition and to a polyurethane foam obtained from the stabilized polyether polyol.
U.S. Pat. No. 3,280,049 discloses a stabilizer composition consisting of a sterically hindered phenol.
U.S. Pat. Nos. 3,567,664, 3,637,865, 4,010,211, 4,021,385, 4,070,304, 4,265,783 and 4,275,173 disclose stabilizer compositions consisting of mixtures of sterically hindered phenols with substituted diphenylamines.
U.S. Pat. No. 3,969,315 discloses a stabilizer composition consisting of a mixture of an alkyl phenyl propylene glycol phosphite and either a hindered phenol or an amine.
U.S. Pat. No. 4,794,126 discloses a stabilizer composition consisting of a mixture of a diaryl arylenediamine, a sterically hindered phenol and the reaction product of a diarylamine with a lower alkyl ketone.
U.S. Pat. No. 4,933,374 discloses a stabilizer composition derived from a mixture of 2,6-di-tert-butyl-4-sec-butylphenol and the reaction product of diisobutylene, styrene and diphenylamine and, optionally, trihydrocarbyl phosphite as color stabilizer.
U.S. Pat. No. 5,077,321 discloses a stabilizer composition consisting of a mixture of at least two compounds selected from a thiophenol, a diphenyl sulfide and a diphenylamine.
The use of various phosphites in stabilizer compositions is discussed in Capolupo et al., "The History and Trends of Phosphites in the Plastics Industry," in History of Polymeric Composites: Invited Papers Presented at the American Chemical Society Symposium on the Origin & Development of Polymeric Composites, Anaheim, Calif., September, 1986, ed. by R. B. Seymour & R. D. Deanin (1987). Tris(nonylphenyl)phosphite, distearyl pentaerythritol diphosphite, bis(2,4-di-t-butylphenyl)pentaerythritol diphosphite, and tris(2,3-di-t-butylphenyl)phosphite are disclosed, inter alia, as antioxidants useful in the manufacture of various plastics.